<!DOCTYPE HTML>
<html>
<head>
<meta charset="utf-8">
<script type="text/javascript">

window.onload = function() {
  setup("1");
  setup("2");
}

function setup(id) {
  var c = document.getElementById(id);
  var names = ["webgl", "experimental-webgl"];
  for (var i = 0; i < names.length; ++i) {
    gl = canvas.getContext(names[i]);
    if (gl) {
      break;
    }
  }
  gl.clearColor(1,0,0,1);
  gl.clear(gl.COLOR_BUFFER_BIT);
  setTimeout(function() {
    gl.enable(gl.SCISSOR_TEST);
    gl.scissor(0,0,50,50);
    gl.clearColor(0,1,0,1);
    gl.clear(gl.COLOR_BUFFER_BIT);
  }, 500);
}
</script>
</head>
<body>
<canvas id="1"></canvas>
<div style="height:4000px;">content that is tall like several articles</div>
<canvas id="2"></canvas>
</body>
</html>

